Synthesis, characterization and antibacterial studies of a copper(II) lomefloxacin ternary complex

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Patricia Fernandes (Author) Other; Isabel Sousa (Author) Other; Luis Cunha Silva (Author) Other; Mariana Ferreira (Author) Other; Baltazar de Castro (Author) FCUP; Eulalia F Pereira (Author) FCUP; Maria J Feio (Author) Other; Paula Gameiro (Author) FCUP

Journal

Title: Journal of Inorganic Biochemistry

Vol. 131

Pages: 21-29

ISSN: 0162-0134

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 44 Citations

Scopus - 44 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-008-GSV

DOI: 10.1016/j.jinorgbio.2013.10.013

Abstract (EN): Solution behavior of lomefloxacin (lmx) complexes with copper(II) in the presence and absence of 1,10-phenanthroline (phen) was studied in aqueous solution, by potentiometry. The results obtained showed that under physiological conditions (micromolar concentration range and pH 7.4) only copper(II):lmx:phen ternary complexes are stable. Hence, a novel copper(II) ternary complex of lomefloxacin with the nitrogen donor heterocyclic ligand phen was synthesized and characterized by means of UV-visible and IR spectroscopy, elemental analysis and X-ray crystallography. In the synthesized complex (1), [Cu(lmx)(phen)(NO3)]center dot 5H(2)O, lmx acts as a bidentate ligand coordinating the metal cation, in its anionic form, through the carbonyl and carboxyl oxygens and phen coordinates through two N-atoms forming the equatorial plane of a distorted square-pyramidal geometry. The fifth ligand of the penta-coordinated Cu(II) center is occupied axially by an oxygen atom from the nitrate ion. Minimum inhibitory concentration (MIC) determinations of the complex and comparison with free lomefloxacin in various E. coli strains indicated that the Cu-complex is an antimicrobial which is as efficient as the free antibiotic but strongly suggest that the cell intake route of both species is different. Moreover, spectrophotometric stability studies suggest that the solution of the complex synthesized is considerably more photostable than the free fluoroquinolone supporting, therefore, the complex's suitability as a candidate for further biological testing in fluoroquinolone-resistant microorganisms with possible reduced side-effects.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9